Lookie here... you got your retracts already pre-cut!

Kidding aside, grab them wings, patch the balsa, some Monocote trim (self adhesive kind) to cover the balsa and your golden! Had to fix a similar hole on my brother's Avistar.

Shouldn't take you more than an hour or two to complete. Just for your info though... the balsa used is not the same as American sized (1/16, 1/8...etc). They seem to use metric when putting it together in China or Whereverland so you'll end up with a slight lip when you join on a spar. No matter just sand it down a bit and you'll be fine.